1. Technical Field
This invention relates to heaters and, more particularly, to a microprocessor based controller for a diesel fuel fired heater.
2. Discussion
Diesel fuel fired heaters include air and coolant heaters using diesel fuel as their primary fuel supply. The diesel heaters provide an independent heat source for any system having diesel fuel and battery power available. Diesel heaters have been utilized in many varied areas such as auxiliary heat in a treatment area of an ambulance, replacement of engine idling as a primary heat source for an engine and a cab of a diesel truck during layovers, deliveries, breaks, etc.
Use of the diesel heaters is expected to increase as the EPA enacts more stringent requirements for diesel engine emissions and fuel efficiency and as the cost of fuel increases. Under these future conditions, truck drivers will be less inclined to leave their engines idling during breaks, layovers, and deliveries while still requiring cab and engine heat. Furthermore, the EPA requirements will lead to the introduction of new and more efficient engines which typically produce less heat that can be transferred for use in other areas.
Existing controllers for diesel fuel fired heaters lack many desirable and necessary features. While existing controllers have timers for automatic starting, they lack automatic starting based on coolant temperature. Some controllers indicate failures encountered during use through a sequence of flashing lights which are not stored for later retrieval. Service personnel may not be present when the sequence of flashing lights occur. In addition, prior failures can provide clues as to causes of later failures.
In summary, more sophisticated controlling techniques for the diesel heaters are desirable.